Scheduling : Backward

Hi all ,

I have FG contains SFG

I am doing backward scheduling .

after MRP , in MD04 the planned order dates and time r as follows :

For FG : date time

Order finish : 30.03.2008 17:30:00

Order start : 23.03.2008 12:50:00,

and for SFG actually the dates the system is giving :

Order finish : 23.03.2008 17:30:00

Order start : 23.03.2008 10:30:00,

Now the requiremnt here is Order finish of SFG should be one day before , that is 22.03.2008 , i am trying with Sch margin Key as :

Flt before prodn : 1 day & float after prodn : 1 day , what i have to use so that i can get one day Gap ?

Regards